Willingham uses a process-costing system for its single product, which is manufactured from Material X and Material Y. X and Y are introduced to the product as follows: Material X: Added at the beginning of manufacturing Material Y: Added at the 75% stage of completion The company started and completed 40,000 units during the period, and had an ending work-in-process inventory amounting to 8,000 units, 20% complete. Which of the following choices correctly expresses the total equivalent units of production with respect to Material X and Material Y? Material X Material Y

A. 46,000 41,600

B. 46,000 46,000

C. 48,000 40,000

D. 48,000 41,600

E 48,000 46,000

The answer is supposed to be C, but according to my calculations with the weighted average method it is D. 48,000 - 41,600. Is this a typo or am I totally lost.. Thanks,